Over the past few days, I've been getting pain in my legs. Its extremely mild, and usually only lasts on-and-off for about 15 minutes. Sometimes its knee pain, but sometimes it's a different kind of pain (similar toa mildly sprained ankle) that runs from my groin to my knee. The pain's really mild and doesn't affect my day-to-day actions. I'm 20, really thin, and lately have been very inactive. Could this contribute to this pain? SHould it be of concern?

This is something that is impossible to diagnose over the internet. It could be something very mild (a pulled muscle) or something very serious (DVT) that only a doctor can advise you on.

Please make an appointment with your doctor as soon as possible.

Agree with J_9... although it is relatively unlikely, DVT (Deep Venous Thrombosis) is a possibility and should be considered until ruled out since it has some very serious complications (pulmonary embolism, death, etc.). There may be some swelling and possibly some redness and warmth in the affected leg with DVT - but not always. Recommend you see a physician without delay.